Micro-Electro-Mechanical-System (MEMS) devices include MEMS pressure sensors. A MEMS pressure sensor measures pressure, e.g., by measuring movement of a pressure sensing diaphragm.
As the pressure sensing diaphragm moves, a change in capacitance between the pressure sensing diaphragm and a fixed electrode is measured. This change is capacitance is used to calculate the pressure.
The change in capacitance is single-ended, i.e., is a single change in capacitance between the pressure sensing diaphragm and the fixed electrode. This single-ended change in capacitance is non-linear with respect to the pressure change and has limited sensitivity in cases where the MEMS pressure sensor has limited sensing area. Accordingly, it is difficult to accurately measure the pressure.
The present invention is illustrated by way of example and is not limited by the accompanying figures, in which like references indicate similar elements. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale.